Tanzania Maize Yield Forecast

RHEAS forecasts

Load and aggregate RHEAS simulated Leaf Area Index (LAI), Water stress and Grain Weight Average Dry (GWAD) across different ensembles. Extract year from dates (we will use harvest year).

Metrics aggregagation

Aggregate RHEAS production forecasts and metrics with respect to Districts maize growing calendar.

We assume three maize growing seasons in Tanzania:

1. Season 1: OND (SRSD) October – February.
2. Season 2: MAM March – September.
3. Season 3: Long Rain (LR) November – April

So we will aggregate the metrics and yield forecast per district with this condition using the function RH_metrics.

Convert RHEAS yields from kg/ha to MT/ha.

Visualization

Add shapefile for visualization.

## Warning: multiple methods tables found for 'approxNA'

Check and format Region names to be consistent in both the RHEAS and administrative boundaries. Here we check which regions are mission from RHEAS predictions.

## [1] "PEMBA NORTH"

Merge RHEAS and Admin data.

Map of yields

Visualize RHEAS predicted yields spatially for all seasons.

## Warning: multiple methods tables found for 'crop'

## Warning: multiple methods tables found for 'extend'

Annual Seasonal Trends

Visualize maize yield trends for the last 15 years.

## Warning: package 'ggplot2' was built under R version 4.1.3

Visualize yields per region between 2000-2022.

par(mai=c(1,2,1,1))
boxplot(rh$gwad ~ rh$Region, las=1, cex.axis=.75, horizontal=TRUE, xlab="Yield (MT/ha)", ylab="", cex=.5, col=rainbow(length(unique(rh$Region))))